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Waze Bug or Wiki Inaccurate on Restricted Turns

Post by aBshield
Over in NJ, we're seeing some examples where restricted turns seem to be treated as absolute restrictions (will never be routed through) instead of being based on the routing penalty system. From reading the article on soft and hard turns, it says a hard restricted turn should apply a high penalty to routing through that turn; "Waze will generally not route through this turn." From reading this I'd assume some penalty (which can change and is proprietary to Waze) is assigned to the turn such that alternate routes are considered, potentially going miles around the restricted turn in extreme cases. Given the nature of a penalty system, I'd further assume in the case where there's only one possible route that Waze will still route through the turn since no other route with a lesser penalty / duration could be computed. This is common with private road transitions and their usage around private installations.

Analyzing the effects of turn restrictions in a normal road network would be difficult since alternate routes are usually plentiful and the penalty strength is always subject to change. Dead-ends better expose the functionality given the lack of other routing options, and we've spotted a few examples. The result is usually the route ending before the destination since Waze seems to refuse to route through the turn restriction, even if the turn restriction is the only access. This implies that all turn restrictions are absolute, and not based on the penalty system, which conflicts with the wiki.

Here's an example. This segment's right turn into Salmon Ln is a legal turn, and is improperly marked as restricted. It's also the only way to access Salmon Ln. Routing to any address in Salmon Ln results in the route ending on US-46 W or most disruptively this private road. My understanding of penalties and following the wiki guidance suggests the route should still proceed into Salmon Ln despite the high penalty, since there are no other valid routes.

Another example here. Once again routing to any address on Quaker Hill Ln will result in the routing ending at this junction node. This example is less severe since this would be close enough for a Wazer to find their way, but the concept is the same: no routing through the restricted turn.

The wiki guidance as written makes sense having all routing be dependent on a penalty system (instead of absolutes). IMHO, this helps to better handle map mistakes that do happen, while still preserving the intent of map editors. If an absolute is required, the segment could just be disconnected, which the wiki also mentions. While this is "how it should work" in my mind, that doesn't appear to be the case. I'd like to discuss further, especially if this behavior is intended and the wiki should be edited accordingly.
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Post by aBshield
CBenson wrote:Yes, you are correct. The hard turn restriction was a penalty that in the past would be routed through to reach the nearest segment to a destination. However, this has changed and waze will now look for other nearby segments to terminate a route when the closest segment cannot be reached due to hard turn restrictions. The wiki could use some updating.
Thanks for the clarification. The part about the route terminating on the nearest segment should probably be mentioned on the wiki as well. In some cases, this is a problem to watch out for and makes improper turn restrictions a higher priority to address in my mind.
CBenson wrote:
aBshield wrote:This is common with private road transitions and their usage around private installations.
I don't understand this point. Private installation are not usually handled with hard turn restrictions.
This was a bit confusing. I was merely trying to equate turn restriction penalty to how private road segments use penalty. All entrances to a private installation can have a high penalty, but the route will still go through the path of least penalty. This allows routing in, but not through, installations etc. This is moot considering your reply that turn restrictions no longer use penalty.
CBenson wrote:
aBshield wrote:The wiki guidance as written makes sense having all routing be dependent on a penalty system (instead of absolutes). IMHO, this helps to better handle map mistakes that do happen, while still preserving the intent of map editors. If an absolute is required, the segment could just be disconnected, which the wiki also mentions. While this is "how it should work" in my mind, that doesn't appear to be the case. I'd like to discuss further, especially if this behavior is intended and the wiki should be edited accordingly.
I think the wiki should be edited. I'm not expecting a change back in the turn restriction behavior. The current behaviour was implemented after much complaints that hard turn restrictions really should mean that the turn is impossible. Disconnecting the segments is not always a viable solution. Take the left turn that is prohibited because of the concrete divider in the median. The segment shouldn't be disconnected as the right turn is possible. But waze should never route through the concrete barrier in the median.

I would suggest editing the wiki to read something like this: https://wiki.waze.com/wiki/User:CBenson/Soft_turns
Understand. I'm sure this was an interesting debate I probably would have been on the other side of. Regardless, I'm not here to debate it now; just wanted to know how it works. Thanks for the info!

Is there a process for changes to the wiki? You've proposed a draft. Not sure where to go from here.

Either way, I'd also suggest changes to the table on the four states and removing the references to penalty. That's assuming that soft turns have the same absolute characteristics and are not still penalty based. Is this known? I realize this state can't be set explicitly, but it just goes to how important these are to fix in the overall priorities, especially when unlocks are needed.
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Post by aBshield
voludu2 wrote:The table says Waze will generally not route through a hard-restricted turn.
Is there any situation in which Waze will route through a hard-restricted turn?
Do we even need the "more information" column anymore? At a minimum, the "more information" for Hard Restricted needs revision on https://wiki.waze.com/wiki/User:CBenson/Soft_turns as you point out.
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Post by aBshield
Glad we have confirmation on this. I assume no further examples are necessary and will proceed with fixing some of these erroneous turn restrictions, unless anyone sees a problem.

Also, did/should we address routing to the closest segment anywhere? The first example in my OP is a great example of where this can be an issue.
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Post by aBshield
CBenson wrote:If we say this on the page we could then point out that a result of erroneously restricting all turns onto a segment is that it will not be used as the destination for any routes. Does this sound correct to everybody?
I think this is a point worth making so the consequence of making an error like this is explicitly mentioned.
PesachZ wrote:What does waze do when the destination is closest to a connected segment with all inbound turns restricted. Will it route to the junction, the next closest segment, something completely random, or fail entirely?
I haven't corrected either of the two examples my original post identified just in case we wanted to look back at the behavior. For certain addresses on Salmon Ln, Waze will take you past Salmon Ln and on to the next segment that's closest (which happens to be a private segment), which really isn't ideal at all. The second example with Quaker Hill Ln stops at the junction, but I hypothesize that's because the end of the segment before is still the closest segment given the road layout in that area.

The first example, while minor in the grand scheme of things given the size of the street and number of addresses on it, really demonstrates when this situation goes wrong.
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Post by aBshield
CBenson wrote:Here is a further revision of the proposed page with a paragraph on routing. https://wiki.waze.com/wiki/index.php?ti ... did=131148
This looks good to me. Should we pull the trigger on this? I'd like to correct the original examples if we're done with them.

I also just noticed that several sections of the penalties wiki page will also need revision.
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Post by aBshield
CBenson wrote:I would think so.
Ok, just checking.

I almost forgot. Not to open another can of worms, but there's some ripple effects from this new understanding of turn restrictions. I think this got lost earlier in the thread:
aBshield wrote:I also just noticed that several sections of the penalties wiki page will also need revision.
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Post by aBshield
CBenson wrote:Yes, we keep talking about an overhaul for that page, but I guess its really time to do something about it.
I was about to copy the current Routing_penalties page and start suggesting changes, but I see CBenson is on it. Here's the continuation of the discussion, just for linking purposes in case anyone else like me missed it. The penalties wiki page has also been flagged directly with this link.
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Post by CBenson
Yes, you are correct. The hard turn restriction was a penalty that in the past would be routed through to reach the nearest segment to a destination. However, this has changed and waze will now look for other nearby segments to terminate a route when the closest segment cannot be reached due to hard turn restrictions. The wiki could use some updating.
aBshield wrote:Given the nature of a penalty system, I'd further assume in the case where there's only one possible route that Waze will still route through the turn since no other route with a lesser penalty / duration could be computed.
This is no longer the case.
aBshield wrote:This is common with private road transitions and their usage around private installations.
I don't understand this point. Private installation are not usually handled with hard turn restrictions.
aBshield wrote:This implies that all turn restrictions are absolute, and not based on the penalty system, which conflicts with the wiki.
Argeed.
aBshield wrote:The wiki guidance as written makes sense having all routing be dependent on a penalty system (instead of absolutes). IMHO, this helps to better handle map mistakes that do happen, while still preserving the intent of map editors. If an absolute is required, the segment could just be disconnected, which the wiki also mentions. While this is "how it should work" in my mind, that doesn't appear to be the case. I'd like to discuss further, especially if this behavior is intended and the wiki should be edited accordingly.
I think the wiki should be edited. I'm not expecting a change back in the turn restriction behavior. The current behaviour was implemented after much complaints that hard turn restrictions really should mean that the turn is impossible. Disconnecting the segments is not always a viable solution. Take the left turn that is prohibited because of the concrete divider in the median. The segment shouldn't be disconnected as the right turn is possible. But waze should never route through the concrete barrier in the median.

I would suggest editing the wiki to read something like this: https://wiki.waze.com/wiki/User:CBenson/Soft_turns
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